Flooding is expected in York after melting snow and heavy rain caused the River Ouse to rise.
There has already been some overflow in the King's Staith and Queen's Staith areas on the banks of the river.
An alert has been issued for Queen's Staith Road, and a more severe warning at Naburn Lock.
Lower-level alerts are in force for the tidal Ouse near Selby, the Derwent near Stamford Bridge and Wilberfoss, and the Nidd near Kirk Hammerton.
There has been some localised flooding in the village of Pannal, near Harrogate, this morning due to a blocked culvert.